From the moment he first laid eyes on his son, Jon Arryn knew he was different. It was the eyes, his own brown eyes that stared back at him with quiet strength. They were too sharp, piercing like daggers. "Truly, like a hawk" he mused to himself.
Unfortunately, the birth had been too much for his wife's body and she had died for her child to live. Nonetheless, Jon was overjoyed to have a son and was resolved to raise him to be a true Arryn of the Vale. As he had promised his late wife. And so it was that the honorable third Hokage of Konoha, Sarutobi Hiruzen, was reborn as Hinrik Arryn.
The boy proved to be prodigious in many a field, speaking fully by 2 years of age and learning to read not much later. Once he could read he began to attack every book he could find with a singleminded intensity, and by the time he was 5 Jon had decided that his son was mature enough to begin learning the trials of being a lord. Hinrik was a joy for Jon to teach, seemingly already aware of the importance of their lessons. He had already developed a commanding aura befitting of a lord and Jon already felt quite confident that the next lord of the vale would be a great man. What was most impressive about his son though, was his perceptiveness. Jon could boldly state that his son was the most perceptive person he had ever met. His son could sniff out a lie that even the person telling it believed. He had once even seen his son derive the birthplace and age of a hedge-knight without ever speaking to the man. Hinrik was certainly different, but Jon had long since adapted to his sons oddities.
Things continued in much the same way until Hinrik was 8. It was then that he took on two boys to foster. Their names were Eddard Stark and Robert Baratheon. Robert was a boisterous boy who didn't take much seriously, while Eddard, or Ned, had a stoic, serious attitude that hid a very caring and loyal heart. The two had already begun to form a close bond and Jon was unsurprised to see that his own son had already begun ingratiate himself to them. It was later that same year that Jon finally relented to his son's pestering and let him begin weapons training. Truthfully, Jon was sure his son could have started training much sooner, but a father was allowed to coddle his son every now and then.
Hinrik took to his martial training well, though he had a few oddities, the first of which was his taste in weaponry. His son proved to be quite gifted with a spear and even more oddly, always seemed to have a small armory's worth of knives hidden away on his person. Jon might have tried to get him to learn the sword, or bow as well but given his sons talent for his chosen weapon, he let him focus on the spear. Hinrik would always push himself hard, once again displaying his drive and by the next year he had begun to spar with Ned and Robert. He still was no where near as strong as the boys, who were both 4 years older than him and built quite strongly. Still, Hinrik made up the difference in strength by being ruthlessly efficient in every spar, never drawing out a fight if he had the chance to end it.
It was through sparring with Robert, that the two boys were finally able to make more of a connection, though it would never be as deep of a bond as they both shared with Ned.
Hinrik had always been closer to Ned than Robert, and before he proved to be a good opponent, Robert had little interest in the younger boy besides a general fondness.